113 citations · 418 across the 29 of their papers we have counts for
5 papers · 1 filter
Periodic variability of the z=2.0 quasar QSO B1312+7837
M. Minev, V. D. Ivanov, T. Trifonov +6
We report here the first results from a 15-yr long variability monitoring of the z=2.0 quasar QSO B1312+7837. It shows luminosity changes with a period P~6.13 yr (P~2.04 yr at rest…
New data for the LBV in NGC 4736
Y. Solovyeva, A. Vinokurov, A. Kostenkov +3
We present new spectral and photometric data of confirmed LBV star from the NGC4736 galaxy. The star NGC4736_1 (Mbol = -11.5 mag) showed noticeable spectral variability from 2015 t…
The Transient Ultra-luminous X-ray Source, ULX-4, in M51
S. Allak, A. Akyuz, İ. Akkaya Oralhan +6
We present the results of a temporal and spectral analysis of the transient source ULX-4 in the galaxy M51. The data used were drawn from Chandra, XMM-Newton and Swift-XRT archives…
Ultraluminous X-Ray Sources
S. N. Fabrika, K. E. Atapin, A. S. Vinokurov +1
Ultraluminous X-ray sources (ULXs) were identified as a separate class of objects in 2000 based on data from the Chandra X-Ray Observatory. These are unique objects: their X-ray lu…
Optical Counterparts of ULXs in Two Dwarf Galaxies: NGC 4861 and NGC 4449
M. Ozdogan Ela, A. Akyuz, N. Aksaker +7
We present the results of a search for optical candidates of Ultraluminous X-ray sources (ULXs) in two dwarf galaxies: NGC 4861 and NGC 4449 using Hubble Space Telescope {\it HST}…